DE69504683T2 - FLOWABLE SALAD SAUCE - Google Patents

Abstract

A pourable acidic dressing comprising 0-50 wt.% of fat, 46-99 wt.% of water, pieces of vegetables, herbs and/or spices of a visible size, an acidulant enough for a titratable acidity of 0.5-2.5 %, 0.1-4 wt.% of one or more non-starch polysaccharides present in a sheared gel form, which polysaccharides used either singly or in combination, if applied under quiescent gelling conditions, at the concentration used in the dressing composition, and at the appropriate pH, titratable acidity and salt content, are capable to form in water either a rigid thermoreversible gel or a rigid chemically set gel or a rigid synergistic gel, where the dressing has a Brookfield viscosity of 100-4,500 cps. (centipoise) and a yield stress (tan delta = 1) of 0.1-10 Pa.

Description

The present invention relates to flowable or pourable products, in particular to flowable acidic food products of the sauce type and more particularly to flowable salad dressings of low viscosity which nevertheless have particulate-suspending properties.

BACKGROUND OF THE INVENTION

Many attempts have been made to formulate good quality salad dressings. In particular, there is a need for flowable products with good appearance and physical properties at all fat contents from 50% by weight down to fat-free products. Flowable two-phase sauces (up to 50% by weight fat) have aqueous phases that do not normally suspend bits of herbs, vegetables and spices. Current shelf-stable low-fat/fat-free sauces typically use xanthan gum to keep bits of herbs, vegetables and spices suspended. However, the presence of xanthan gum results in a viscosity that is undesirably increased compared to homemade, non-shelf-stable or full-fat products. Shelf-stable means that the bits of vegetables, herbs and/or spices remain suspended for at least 4 weeks. The use of xanthan gum also leads to poor surface coating properties and a slimy mouth feel. Therefore, a drastic reduction and especially the absence of xanthan gum from pourable salad dressings is highly desirable.

EP 558 113 contains the description of a general process for water-continuous compositions Finally, salad dressings containing polysaccharides in the form of microgels obtained by applying shear during gelation.

STATEMENT OF THE INVENTION

Flowable shelf-stable salad dressings have been found which, in the absence of effective amounts of xanthan gum, have a surprising ability to keep bits of herbs, vegetables and/or spices suspended for a prolonged period of time. This suspension effect is achieved at a viscosity even lower than the minimum viscosity necessary to impart bit-suspending properties to current xanthan-based vinegar and oil dressings.

According to a first aspect of the invention there is provided a flowable sour sauce comprising:

a. 0 to 50% fat by weight,

b. 46 to 99 wt.% water,

c. Pieces of vegetables, herbs and/or spices of a visible size,

d. an acidifying agent sufficient to provide a titratable acidity of 0.5 to 2.5%,

e. 0.1 to 4% by weight of one or more non-starch polysaccharides present in a sheared gel form,

which polysaccharides, used either individually or in combination, when used under quiescent gelling conditions, at the concentration used in the sauce composition and with appropriate pH, titratable acidity and salinity, are capable of either:

(A) a rigid, thermoreversible gel or

(B) a rigid, chemically hardened gel or

(C) a rigid, synergistic gel

to build.

The final sauce has a Brookfield viscosity of 100 to 4,500 cps (centipoise) and a yield stress (tan delta = 1) of 0.1 to 10 Pa.

"Quiet gelling conditions" means that the gel can form in the absence of shear.

It has further been found that such sauces can be obtained if the sauce composition contains specific polysaccharide gels and the sauce is prepared under shear conditions which cause a disruption of the normal polysaccharide network formation.

According to a second aspect of the invention, there is therefore provided a process for producing a flowable salad dressing having the above-mentioned composition and rheology, which process comprises the steps:

a. dispersing the polysaccharides in water to obtain a premix, optionally adding one or more other ingredients, including pieces of herbs, vegetables or spices, to the sauce composition;

b. Applying shear during gel formation;

c. Add the remaining ingredients of the sauce to the sheared gel dispersion so that the final sauce has:

a Brookfield viscosity of 100 to 4,500 cps and a yield stress (tan delta = 1) of 0.1 to 10 Pa.

The sauces of the invention have improved rheology, stability, coating properties and mouthfeel compared to traditional vinegar and oil sauces and prior art sauces containing effective amounts of xanthan gum.

DETAILS OF THE INVENTION

The sauce contains pieces of vegetables, herbs and/or spices of a visible size. Visibility is to be understood as meaning that the pieces can be distinguished as such with the naked eye. This means that at least 80% by weight of the pieces have a size in the range of 0.5 to 5 mm. When such pieces are initially dispersed in a sauce, they normally settle to the bottom of the container after a few hours. Visibility does not mean that the pieces are visible under all circumstances. For example, in an opaque sauce only the pieces on the surface of the sauce are visible. Sauces according to the invention preferably have a Brookfield viscosity in the range of 200 to 2000 cps, especially 200 to 1000 cps. These are the suitable low viscosities for a flowable sauce.

Brookfield viscosity is a common viscosity parameter and is determined by measuring the viscosity after 1 minute of shear at 10 rpm using a Brookfield DV-I+WZ viscometer equipped with an RV spindle set.

Sauces according to the invention preferably have a yield stress (tan delta = 1) in the range of 0.2 to 5 Pa, in particular 0.2 to 2 Pa. This yield stress ensures good lump-suspending properties. It is determined by performs an oscillating stress ramp using a Carrimed CSLWZ 500 rheometer and a standard geometry and determines the stress value at which the tangent of the delta function becomes one (tan delta = 1). This procedure allows a comparison of different materials in the same deformation state.

The determination of viscosity and yield stress is carried out at a temperature of normal product use, which is generally 5 to 35ºC, but typically 18 to 25ºC.

In the preparation of the sauces according to the invention, shear is applied during the gel formation leading to microgel particles. To achieve the desired rheology, the appropriate shear conditions can be determined by conventional variations known to those skilled in the art. In general, a relatively high shear is used.

Shear can be applied by various means, for example by using a homogenizer, high shear mixer, votator or thin film heat exchanger. There must be sufficient tolerance to allow substantial passage of granules up to about 5 mm in size. Sufficient tolerance is obtained by using a thin film heat exchanger with rotors of suitable size to allow an annular spacing of at least 5 mm for the product. Greater spacing can allow greater granule integrity. Smaller spacing will not allow homogeneous distribution of granules and will destroy granule integrity. Suitably a ConthermWZ thin film heat exchanger, model 6x3a, is used at a product temperature of 5ºC, at a throughput of 1.5 to 4.0 kg/min and a tip speed of 1.5 to 10 m/s, preferably 2.0 m/s. When using other shearing devices to achieve a product with the desired rheology and surface coating properties, the person skilled in the art will be able to determine suitable shear conditions which are at least equivalent to the shear conditions of the ConthermTM device.

All sauce ingredients can be added to the premix before shearing begins ("all-in-one process"). However, to prevent possible breakage of the pieces, the herb, vegetable and spice pieces are preferably added after the gel dispersion has been formed.

According to a preferred embodiment, the sauce premix is subjected to a pasteurization treatment before shearing.

The gels usable for the invention are selected from the group consisting of thermoreversible gels, chemically solidified gels and synergistic gels.

For the purpose of the invention, the term thermoreversible gels refers to polysaccharide gels that melt when heated and regain their gel structure after cooling.

Examples of thermoreversible gels of polysaccharides are disclosed in EP 355 908.

The preferred non-starch polysaccharides for this purpose are agar, iota-carrageenan, kappa-carrageenan and furcellaran. The preferred concentration is 0.5 to 2.0% by weight, in particular 0.7 to 1.5% by weight, with the exception of agar where the content is preferably 0.2 to 2.0% by weight, in particular 0.4 to 1.1% by weight. The gelling temperature of thermoreversible gels is preferably 0 to 85°C, in particular 20 to 50°C.

For the purpose of the invention, the term chemically solidified gels refers to polysaccharide gels that do not melt reversibly after increasing the temperature. They derive their gel structure from the chemical interaction of the polysaccharide with suitable ions, e.g. Ca2+ ions. Examples of chemically solidified gels of polysaccharides are disclosed in EP 432 835.

A suitable non-starch polysaccharide preferred for this purpose is sodium/calcium alginate, the extent of alginate conversion to calcium alginate preferably being greater than 10%, especially 20 to 100%, most preferably 70 to 90%. Regarding the dependence of alginate gel strength on calcium, see Food Gels, pp. 53 to 78 (Ed. P. Harris), 1990, Elsevier ISBN 1-85166-441-9.

Another chemically set gel is low methoxy pectin (DE 5-50) with an R-value in the range of 0.3 to 1.0 (where R is defined as twice the calcium concentration divided by the concentration of free pectinate groups). The desired R-value is obtained by adding an appropriate amount of CaCl2 · 2H2O solution to a pectin solution.

These chemically solidified gels are preferably used in a content of 0.3 to 2.0 wt.%, in particular 0.6 to 1.5 wt.%, most preferably 0.7 to 1.1 wt.%.

Preferred cations for effecting gelation are Ca²⁺ and K⁺, which are used in such an amount that the above conversion rate or R-value is achieved. Normally suitable concentrations are in the range of 0.01 to 1.0 wt.%.

Synergistic gels are described, for example, in Edwin R. Morris, Mixed Polymer Gels, Food Gels, Elsevier Applied Science (1990), 291 to 352. For the purpose of the invention, synergistic gels are intended to include all mixtures of two or more polymers, at least one of which is a non-starch polysaccharide, which may be non-gelling individually but which form gels (or gels of higher moduli) when mixed.

Examples of combinations of polysaccharides capable of forming synergistic gels are

Sodium alginate/pectin,

Agar/Konjac Mannan,

Carrageenan/Konjac Mannan,

Propylene glycol alginate (PGA)/pectin

Agar/locust bean gum and

kappa-carrageenan/locust bean gum.

A gel selected from the group consisting of agar, calcium pectin, calcium alginate, sodium alginate/pectin, kappa-carrageenan and iota-carrageenan is preferred for use in the sauces of the invention.

More preferred is the synergistic alginate/pectin gel, the weight percentage of which is preferably 0.2 to 0.9, especially 0.3 to 0.3, most preferably 0.4 to 0.7.

Particularly preferred is the synergistic gel of sodium alginate/pectin with high methoxy content. The sodium alginate preferably has a high guluronic acid content. The hydroxyl groups of the high methoxy pectin have preferably been methylated to a value of more than 50%, in particular more than 55%, most preferably 60 to 80%.

The alginate:pectin ratios are preferably 30:70 to 90:10, especially 40:60 to 80:20, most preferably 50:50 to 70:30.

The combined weight percentage of alginate and pectin is preferably 0.50 to 4.0 wt%, more preferably 0.70 to 3.0 wt%, most preferably 0.90 to 2.0 wt%.

The alginate/pectin based sauce composition is acidified according to the required titratable acidity (specified later), which is however limited because the (product) pH must be < 4.0, preferably < 3.85, most preferably 3.2 to 3.8.

These synergistic gels are preferably prepared in the substantial absence of Ca2+ cations so that no chemically solidified gels are formed. In the preparation of synergistic gels, the Ca2+ content is preferably 0 to 0.01% by weight, especially 0 to 0.001% by weight. The most preferred compositions according to the invention are essentially free of Ca2+. By reducing the content of calcium ions, the taste of the sauce is improved.

The water used to make the sauce is preferably free of calcium, e.g. by using deionized or demineralized water.

Although the compositions of the invention are preferably substantially free of xanthan, it is known small amounts of xanthan gum to minimize water separation, and these small amounts can be used on condition that they have no adverse effect on the rheology mentioned above. Therefore, some xanthan gum is permissible in a content of 0 to 0.1 wt.%, preferably 0 to 0.01 wt.%.

Sauces are essentially food compositions with an acidic taste. An acidulant is incorporated to impart the desired taste and aroma and for microbiological preservation. Suitable acidulants include acetic acid, lactic acid, citric acid and phosphoric acid. Vinegar and acetic acid are the preferred acidulants for sauces. The optimal amount of acidulant is determined by sensory evaluation and microbiological stability. It is known that a sensory evaluation does not have a good correspondence with the pH of the sauce because components, e.g. proteins, can interfere with the acidity perception. A better parameter for measuring acidity is the so-called titratable acidity (TA). Titratable acidity is the amount (g) of titratable acid based on the total amount (g) of the sauce * 100%. The titratable acidity is 0.5 to 2.5%, preferably 0.9 to 1.8%, and most preferably 1.1 to 1.4%. A method for measuring the titratable acidity is included in the examples below.

Compositions according to the invention can comprise 0 to 50% by weight fat. The fat content is preferably 0 to 15% by weight, most preferably fat contents of 0 to 10% by weight, including essentially fat-free sauces and sauces with a fat content of only 0.5 to 8% by weight. However, the invention also enables the preparation of sauces with 30% fat, e.g. full-fat Italian sauces.

Throughout the description, the terms oil and fat are used interchangeably. Non-digestible fats, such as sucrose polyesters, may also be used.

Fats for use in the sauces according to the invention are preferably liquid at room temperature. Their SAFA content is ≤ 15 wt%. Traditional salad dressing oils or other suitable naturally occurring oils or mixtures thereof can be used, e.g. olive oil, linseed oil (about 10 wt% SAFA), rapeseed oil (about 9 wt% SAFA), safflower oil (about 9 wt% SAFA), sesame oil (about 9 wt% SAFA). Oils obtained from (genetically) modified sources can also be chosen. It is also possible to obtain oils with low SAFA content by fractionating and/or modifying naturally occurring oils. An example of an oil with very low SAFA content and its method of preparation are disclosed in EP 326 198.

The invention also enables the preparation of a shelf-stable sauce that allows an oil phase as a separate layer in addition to an aqueous phase containing suspended particles. After shaking, both phases form an emulsion with a viscosity and surface coating properties similar to traditional vinegar and oil sauces without xanthan. Droplets of the oil phase in the shaken sauces of the invention remain substantially dispersed for at least 1 hour. This is superior to traditional sauces and xanthan-containing sauces of the same viscosity. Traditional sauces refer to homemade and non-shelf-stable sauces.

In a preferred embodiment, the fat is in a stable emulsified form containing small fat globules with a volume-weighted mean diameter of less than 20 µm, in particular 0.1 to 5 µm, most preferably 0.5 to 2 µm.

The compositions according to the invention contain water in a content of 46 to 99 wt.%, preferably 60 to 95 wt.%.

If desired, the compositions of the invention may contain other gelling or thickening agents in addition to the preferred gels mentioned above.

Examples of such materials are non-gelling hydrolysed starch, amylose, denatured whey protein, denatured soy protein, locust bean gum, guar gum, gum arabic and microcrystalline cellulose. The total content of these additional gelling and/or thickening ingredients is preferably 0 to 10% by weight, more preferably 0 to 5% by weight, most preferably 0 to 0.5% by weight. However, for taste reasons, the sauces are essentially free of these ingredients.

According to a further embodiment, a sheared gel with the composition of the sauce according to the invention can be diluted either with water or with the aqueous phase composition in order to adjust the parameters of the finished product so that they correspond to the claimed ranges.

Optional ingredients of the sauce according to the invention also include: flavors, salts, preservatives, vitamins and coloring materials, which are to be added in the usual amounts. Suitable concentrations are: salt (e.g. sodium chloride) 0 to 4% by weight, preservatives (preferably potassium sorbate and sodium benzoate) 0 to 4% by weight, coloring material (e.g. beta-carotene) 0 to 1% by weight.

The low-fat/fat-free, flowable sauce of the invention has several advantageous properties. The sauce contains pieces of vegetables, herbs and/or spices of a visible size. Although essentially xanthan-free, the consistency of the sauces allows the pieces to be kept suspended for at least 4 weeks. Furthermore, the sauce has good rheological and surface coating properties. The slimy mouthfeel of xanthan-based sauces is significantly reduced or even eliminated.

The sauce according to the invention also shows an increased emulsion stability when oil is present and also a better surface coating behavior when poured on salad.

The sauce according to the invention forms a suitable basis for the production of, for example, "Italian", "French" sauces or vinaigrette-type sauces.

The invention is further illustrated by the following examples:

Titratable acidity (TA)

The titratable acidity is the amount (g) of titratable acid related to the total amount (g) of sauces * 100%. It is determined as follows:

Disperse a sample of 5 to 10 g of a salad dressing containing e.g. acetic acid as acidulant in 100 ml of distilled water and stir; titrate with 0.1 N sodium hydroxide (adjust the measuring device to pH 8.1 using a two-point standardization technique and standardize with a pH 7.00 buffer) to pH 8.1 after stabilization for 30 seconds (A ml); perform the same steps for distilled water instead of salad dressing (B ml). The TA (%) = [(C * (A - B) · 0.1 / exact sample weight)] * 100%. C * 1000 = relative molecular mass of the acid divided by the number of dissociated acid groups in the molecule (for e.g. acetic acid C = 0.060). Compare: Vogel, Textbook for Quantitative Inorganic Analysis.

Examples 1 to 5

For the type and quantity of the ingredients, see Table I.

A dispersion of the gelling agent in cold water is heated to 85 to 90ºC. Sodium chloride, potassium sorbate and sodium benzoate are added, followed by the liquid flavour components and the vinegar.

The mixture is processed by passing it through a thin film heat exchanger, cooling to a final temperature of less than 10ºC and applying shear so that the gel after formation has a lower modulus than a corresponding gel formed under quiescent conditions, but retaining a yield stress. Pieces of herbs, spices and/or vegetables are added after shearing. The yield stress of the gel system allows these pieces to be kept suspended.

Example 6

Example 6 is carried out as described in the previous paragraph. The processed aqueous part of the sauce is poured into a container and then - on top of this portion - oil is added in the appropriate proportion.

Example 7

Example 3 is repeated, but the herb/spice/plant pieces are added together with the other ingredients before the shearing step.

Comparative examples A, B and C for sauces containing xanthan

For the type and quantity of ingredients, see Table 1.

Xanthan gum is dispersed in cold water. Then sodium chloride, potassium sorbate, sodium benzoate and sucrose are dissolved and finally the flavor mixture, including small pieces such as herbs, vegetables and spices, and the vinegar are added and the mixture is stirred until homogeneous.

The oil portion in Example C is added as described in Example 6.

RESULTS

Table II shows that all the sauces according to the invention have good chunk-suspending properties. The surface coating capacity as well as the flowability and mouthfeel (in particular absence of sliminess) are satisfactory. Even if the chunks of vegetables etc. are added before shearing, the chunks remain suspended in the sauces obtained for at least 4 weeks. The traditional compositions refer to home-made, non-shelf-stable sauce compositions. Table I - Compositions of the examples Table II - Properties of the examples

Claims (13)

1. A flowable sour sauce comprising: a. 0 to 50% fat by weight, b. 46 to 99 wt.% water, c. Pieces of vegetables, herbs and/or spices of a visible size, d. an acidifying agent sufficient to provide a titratable acidity of 0.5 to 2.5%, e. 0.1 to 4% by weight of one or more non-starch polysaccharides present in a gel form subject to shear, which polysaccharides, used either individually or in combination, when used under quiescent gelling conditions, at the concentration used in the sauce composition and with appropriate pH, titratable acidity and salinity, are capable of either: (A) a rigid, thermoreversible gel or (B) a rigid, chemically hardened gel or (C) a rigid, synergistic gel to form, whereby the sauce a Brookfield viscosity of 100 to 4,500 cps (centipoise) and a yield stress (tan delta = 1) of 0.1 to 10 Pa. 2. Sauce according to claim 1 with a Brookfield viscosity of 200 to 2000 cps and a yield stress (tan delta = 1) of 0.2 to 5 Pa. 3. Sauce according to claims 1 or 2 with a titratable acidity of 0.9 to 1.8% and in particular 1.1 to 1.4%. 4. Sauce according to any one of claims 1 to 3, wherein the acidifying agent is vinegar or acetic acid. 5. A sauce according to any one of claims 1 to 4, wherein the gel is selected from the group consisting of agar, calcium pectinate, calcium alginate, kappa-carrageenan and iota-carrageenan and the synergistic gels of sodium alginate with high methoxy pectin and konjac mannan with either agar or carrageenan. 6. A sauce according to any one of claims 1 to 4, wherein the gel is a synergistic gel comprising sodium alginate and high methoxy pectin. 7. Sauce according to any one of claims 1 to 6, which is substantially free of Ca²⁺. 8. A sauce according to any one of claims 1 to 7 which is substantially free of xanthan gum. 9. A sauce according to any one of claims 1 to 8, wherein droplets of the oil phase remain substantially dispersed for at least 1 hour. 10. Sauce according to any one of claims 1 to 9, wherein the pieces of vegetables, herbs and/or spices remain suspended for at least 4 weeks. 11. A process for preparing a pourable sauce, comprising: a. 0 to 50% fat by weight, b. 46 to 99 wt.% water, c. Pieces of vegetables, herbs and/or spices of a visible size, d. an acidifying agent sufficient to provide a titratable acidity of 0.5 to 2.5%, e. 0.1 to 4% by weight of one or more non-starch polysaccharides in a gel form subject to shear, which polysaccharides, used either individually or in combination, when used under quiescent gelling conditions, at the concentration used in the sauce composition and with appropriate pH, titratable acidity and salinity, are capable of either: (A) a rigid, thermoreversible gel or (B) a rigid, chemically hardened gel or (C) a rigid, synergistic gel to form, the method comprising the steps of: a. dispersing the polysaccharides in water to obtain a premix, optionally adding one or more other ingredients, including pieces of herbs, vegetables or spices, to the sauce composition; b. Applying before shearing during gel formation; c. Add the remaining ingredients of the sauce to the sheared gel dispersion, so that the final sauce has: a Brookfield viscosity of 100 to 4,500 cps and a yield stress (tan delta = 1) of 0.1 to 10 Pa. 12. A method according to claim 11, wherein the pieces of herbs, vegetables and spices are added after formation of the sheared gel dispersion. 13. A process according to claims 11 or 12, wherein the sauce premix is subjected to a pasteurization treatment prior to shearing.